Differential-pressure recorder.



W. H. BRISTOL. DIFFERENTIAL rnzssunn nnoonnnn.

APPLIUATIOI FILED KAY 29, 1908.

l Patented Sept. 17,1912.

l 8 IHREN-SHEET 1.

5 vw@ wtoz Wmme/a: gw mi; ZMMMWMM W. H. BRISTOL. DIFFERENTIAL rngssuannnooannn.

PPLXUAIIOI FILED KAY 29, 1008.'

8 lXEBTB-BEBBT R.

Patented Sept. 17, 1912.

Wim/M5 wwMo/c PATENT OFFICE.

WILLIAX B. BRIBTOL'OF'NEW YORK, N. Y., ASSIGNOB'TO THE BRISTOL COMPANY,OF WATEBBUBY,1CONNECTICUT,A CORPORATION OF CONNECTICUT.

DIFERENTIAL-PRESSUBE RECORDER.

appiiemon ma any se,

Bpeeioation of Letters Intent.

Patented Sept. 17, 1912. 190e. serial No. 495,740.

To all whom it may concern.`

Be it known that I, WILLIAM H. Bius'ror.,

a citizen of tlieUnited States, residing at NewYork in the county of NewYork and State of liew York, have invented certain new and useful Imroveinents in Differential-Pressure Recor ers, of which the followin isa specification'. My invention relates to recordingdevices, and moreparticularly to "ardevice for directly recording the diterencesoftwofluid pressure; and 1t has for its objectto make the said deviceindependent of the pressure of the atmosphere or medium in which saiddevice is located, to simplifyv the construction of such devices, andtol avoid the use of stutiing boxes or the like which produce :fric--tion of the.recording mechanism.

For this' pur ose my invention consists of certain novel eatures ofconstruction and, arrangement of parts, as set forth .1n the, specication and shown in the.accompany, in drawiii in whichpressure recorderwitha portion ofr the instrument casing and the .cover of the. pressurecasing removed. Fig. 2,is a sectional view'of the ressure casing. asectional view o a different form o actu-iating` means forvthe recordingarm. ,l Similar characters of .reference designate corresponding partethroughout the several views. n

Referring to the drawings, indicates a protcctinginstrument casingcontaining the usual cloc or other mechanism .,(not shown for rotatingor moving a record lsheet 1 and the actuating mechanism for the'record,ing arm 12. T is actuatingxnechanism is shown entirely housed within apressure cas.

ing 13, secured to the back plate oftheproe; tecting casing 16. In manydesigns of pres. sure recording devices, interme iateftrans'-` mittig;and multiplying mechanism isempl ploy In case such mechanism be employedin 4connection 'with' vthe differential` pressure recorder hereinsetforth thesame may' or may not be contained within the saidy pressurecasing 18. f (iff,

In Iy'igs. 1 and 2 I have shown .as these-1 tiiating means a numberl ofsuperimposed' communicating, expansible4 diaphragme? 11if Fi .Bisy

such as employedin the ressure gages set forth in my prior U. S. Entente#420 570,

822,244, #889,981 and 839,982; an in ig. 8 an ex ansible helical tube 15closed at one end, an open at the other to one of the pressures.

Referring to Figs. 1 and 2, the set of exvpansible iaphragms isrestrained from -moving vertically. and constrained to angular movementby means of flexible bands or by links 16 secured at their upper ends toa iece 17 attached eccentrically to the top of he. set of diaphra ms asset forth in my prior` Patent-#82 ,244. This set of diaphragme isv`securedv at the bottom to the pressure casing' 18, and -vcommunicateswith one of the pressures through the inlet pipe 18. `A second inletpipe 19 communicates directly .with the ressure casin 18. The lowerlyend of one o the links 16 is pivotally ,connected to a rigid pin 16 andnear the .bottom-of the casing 13 as shown; while fthe lower end of theother link is ixedly igure 1 :sa front elevation-of lthe differ-iY entiacnnectedto' a shaft 20 passing through a =sleeve 2 1 end whose axis 1sin line with the vaxis ofthe-pivotal connection of the other link,jthusforming an axis of natural rotation' about. which the said series ofdiaghragms 1s constrained to move. The sleeve 1 is preferably ofconsiderable len th in `pro ortion to the diameter of said con aincd'sha t, and is secured preferably to and ypasses through the removablecover 22 of the reesurecasin l`A shaft of from three to our hundredt isof an inch in diameter with a clearanceof from one to two thousandthsofan .inch has been found satisfactory. At .the inner end of the shaftthis clearance is j referabl increased as by the piece 27, 1.55.3.v heshaft 'passes entirely tlirou li lsaid .sleeve and carries at its outerend tie recording larrri 12, the casing being closed with the exceptionof the said sleeve 21 and the said inlets 18.and 19, which latter conveythe mediums whose differential pressure is to be recorded. The saidsleeve with its yshaft is sealed by means ofa suitable material such'asgrease, lubricant or liquid, and pref- .erably a mineral, non-d ing oilas cylinder cih-.which at the same time acts as a lubricant'lfor theshaft 20 forming a practically frictionless bearing for the said shaft,and

by its capillary attraction and adhesion sealingl` the.` pressure``casing .13e as; a-i wholeq The increased diameter .of i-the sle'eve*lati its innerend affords al convenient means ofi uniformly ap lying the.sealing-material so that it may-Ee distributed throughthe sleeve toforni the seal.

In Fir'. 3, the actuating lnie'ans,"rloeated within the pressure casing23, is'the helical-- tube 15 closed 4at one end 'and securedat the vother to the bottom of thesaideasing and.4 with which one of thepressures'c'mmuniff cates through a suitable inlet.24, the othercommunicating directlylfwith the' casing throu h inlet.25.f"l`o teclosed'endof the helica tube 15 is tixedly secured a' connecting piecebent substantially tothe shape shown and terminatin'gat the'longitudinal axis of the tube, where it is secured to a shaft 26 also inthe axis of the said helical E tube. This'shaft as in thepreviously.'de' scribed form asses throu h a'sleeve'27'ot suitable lengtand secure( to and'passin Y throuch the front cover of th'casing 2,8.`suitalile sealing materialis'held'in said sleeve to seal the sameasinthe former case. A thrust bearing such v`as thejewel `bearing 28 maybe providedffor the'outer eiid of shaft 20, Figa 1 and 2 andvfor ltheshafti Q6, Fig. 3 w ien high pressure'sexist in' thel sealed chamber,in'or'der that the `said shaftsshall not be forced .through .theirrespectiver sealing sleeves due to the high pressureon'- their innerend.I "l" 1.@ ffii.. The pressure in the casin'gs 13 and 2871s@effectively sealed in bothforms, while th` freedom of the movement oftheAactuat-ing shaft and consequently of the' reeordingarii'r is notmateriallyfatleeted.' The"de`vic\e,p,ei" mits of the recording of.extremely -delicate movements resultin from'-l the applicati'i'i of buta very smal actuating pervert-prof.' duced by slight differences of thepresaureil' existing resieetively within tube"orfdia-! piiragiii, an thecontaining sealed'pressure easing. If desired, theipressureycasing-'13,. as we l as the diaphra s 14,or helical-tube 15, may befilled wit a suitable' liquid or liquids, the difference ofwhespressures itis desired to record,` of `wliichfact sim lyl asx a pressure'transmitting medium. fff'thL 'liquid within the pressure chamber-beusedas a transmitting liquid and be ofthe proper' quality it may at-thesaine time serve-'as the sealing liquid.4 It has been found that evenran extreinelyggreaty ressureawill, be perf feetlymaintained wit inthe"ressure-cham# ber, he seal between the'shaf land itsaleeve through caillarvgattraction 'and yadhesion being 'capa le of resisting'extremely.' high-I differences of lpressure,= butr inet'.iproducing;Y

appreciable resistance to.'` rotationff,Yariusi.. otheriappli'cationstvof"this' seal iwilli;readily'.l sug'g'es'tvthemselvesfasffzfor. example:A :toll in-'4 vioscillate such that it is desirable toeliminate the eifectydue toivariations in the surroundingr aama'phare.=wi

The device is simple in its construction, is positiveqin its action andsuitable for the measurement; of thedifferential pressures o i variouskinds of fluid, can be constructed to 'respondto exceedingly slightdifferences olpigssures and is durable and readily porta e.v

`1 am avvare` that various differential pres` sure recorders could bedevised in which .some part of the actuating mechanism might be broughtlthrough-a stuing box containing packing or the like, to seal the'pressurey chamber, but I do not wish to fclaim' that means of sealingthe pressure .chamber asgit is unreliable, cumbersome, fand'produces toomuch friction.

Ielainni '1. In' atdifferential pressure recorder: a seale'd"pressurecasing, and an inlet thereto lfor one of-tlilpressures; 'pressureactuated mechanism-wit ins'id casing, exposed on Ithe outsideto-"thepressure existing in the casin ,arid'constrained to angular motion;an'fin et t'osaid mechanism for the other ot' said pressures and-towhich-the said mecha ,inismisexposed on the inside, whereby said`mechanism is adapted to oscillate proporltionally to varyingdifferencesl between the Vpressures existingin said mechanism and sai'dcasing; a shaft in the axis of oscillationI ofsaid 4ressure actuatedmechanism and thereby; a horizontal 'y pressure sealing tube of smalldiameterrelativelv to iits length, affording-'a substantially fric--itipnlessb'earing forsaid shaft and extendin' through 'a wall of saidcasing, said tube ibeingtadaptedl to retain a ilmo a suitable sealin'gliquid to surround a portion of said fshaft which extends therethrough;and a recording arm outside of said sealed pres- 'Isureizcasing andin\eonneetion with said shaftr i v A 2; 'In a diierential pressurerecorder; a isealedpressure casing, and an inlet thereto forfonepfthepressures; pressure actuated 'mechanismki'wit in' said casing, exposedon ,theoutside'to-the ressure existing in the lcasin (and constrained toangular motion; gan in et to said mechanism for the other ofEsaidpressures and to which the said mechjanisinis exposedvonthe inside,whereby said ymechanism is adapted to oscillate propor- Qtionallytovarying differences between the pressures-existing in said mechanism andsaid casing; a shaft-in the axis of oscillation lof said"y ressureactuated mechanism and ,oscillate thereby; a' horizontal pressureisealingitubetf small diameter relatively to its length, laffording asubstantially frictionlessebearingwifor said shaft and extendingthrough-a-,rjwall of said casing, said tube struments -where the ranges"ofi-pressure fare'z beingsadaptedto retain atilm of asuitahlescaling'liqudtosurrolmd'a portion of said -In testmon whereof I nix mysignature slfmftllwhicl extends 1tharethrough; nlportiou injpresence otwo witnesses.

o ex arve 'interim iameter at t e innev:

end of` sid t-ubto'proyide a reservoir Vfor VILLIAM H' BRISTOL thesealing liquid; and a recording arm outside of said sealed ressure'casngand n connection with sai shaft.

Witnesses:

Fnmnx F. SoHUn'rz, SALLY O. Yumzxr.

Copie: of thu pntent may be obtlinod for nve oontleaoh, by lddreulng theCommissioner ot Patents,

l wlghingt'on, D. 0.

